Russia is likely increasing its stockpile of air-launched cruise missiles, the UK MOD said.
The weapons could be used to strike Ukraine's energy infrastructure this winter, it said.
Last year, Russia bombarded Ukrainian energy targets, cutting off electricity and heat to millions.
This suggests that Russia will likely be able to generate a "significant" stockpile of the weapons and there is a "realistic possibility" they will be used to strike Ukraine's energy infrastructure targets in the winter, according to the UK ministry.
Last winter, Russia conducted mass long-range strikes against such targets, cutting off electricity, heat, and water to millions of civilians.
Organizations:
MOD, Service, UK Ministry of Defence, Atlantic Council
Locations:
Russia, Ukrainian, Wall, Silicon, Kodiak, Ukraine